I just got my account up and running 2 days ago and started submitting proposals. I quickly learned that I don't apply to "Payment Unverified." Every one has been a scam thus far. So I've tailored my search to "Payment Verified" gigs. It was very frustrating though.
Clients can post a job before verifying their payment method and completing their company information with address and other details. Clients need to provide this information first before they can hire a freelancer. So clients who don't have verified payment methods and details about their location are most likely just new.
If the payment method is unverified, this means the client has not yet added a payment method on file and any work done on a contract without a verified payment method will not be covered by payment protection. When communicating with a client prior to accepting the offer or starting work, we recommend freelancers to speak with their clients about verifying their payment method as this would benefit both parties in having payment protections in place.
We do not wish to discourage freelancers from sending proposals to clients who are yet to verify their payment method. However, we always recommend freelancers to be wary of clients who raise red flags and to consider the recommendation I noted above so that they can work safely on Upwork.
I'm sorry to learn about your experience in Upwork. I highly recommend that you read up on the "Safety First!" section of the freelancer resources we have compiled, and these tips for avoiding questionable jobs for more information about working safely through Upwork. Being able to identify red flags on job posts, or during interviews will help you be able to vet potential clients better. If any of the jobs or interviews raises any red flags, you can flag these job posts are inappropriate so that it can be reviewed by the team further.
If you need help with anything, please don't hesitate to reach out.